Question: If $x \triangleleft y = 2x-3y$ and $x \oslash y = (3-x)(y)$, find $-6 \triangleleft (2 \oslash 6)$.
Solution: First, find $2 \oslash 6$ $ 2 \oslash 6 = (3-2)(6)$ $ \hphantom{2 \oslash 6} = 6$ Now, find $-6 \triangleleft 6$ $ -6 \triangleleft 6 = (2)(-6)-(3)(6)$ $ \hphantom{-6 \triangleleft 6} = -30$.